Patch Application System

ABSTRACT

A patch application system is provided comprising a powder application booth. The powder application booth comprises a powder block to temporarily house the powder prior to ejection, a nozzle insert to guide the powder onto the screw, a support stand to adjust the powder block to the appropriate position relative to the screw for a desired patch location and size, a powder cup to deliver the powder to the powder block. A programmable logic controller electronically coupled to the micro air-switch valve controls the duration the air-switch valve remains open. The entire process may be automated by including a screw hopper to temporarily store a plurality of screws, a bowl feeder receiving the screws and delivering the screws to a rotating disk, wherein the rotating disk passes the screws through a heating element and presents the heated screws to the powder application booth.

CROSS REFERENCE

This application is a divisional application of application Ser. No.11/906,305 filed Oct. 1, 2007, titled “A Method of Applying a Patch to aFastener” which is incorporated in its entirety by this reference.

COPYRIGHT NOTICE

Portions of the disclosure of this patent document may contain materialthat is subject to copyright and/or mask work protection. The copyrightand/or mask work owner has no objection to the facsimile reproduction byanyone of the patent document or the patent disclosure, as it appears inthe U.S. Patent and Trademark Office patent file or records, butotherwise reserves all copyright and/or mask work rights whatsoever.

TECHNICAL FIELD

This invention relates to fasteners, particularly, methods and systemsof producing self-locking fasteners.

BACKGROUND ART

One of the problems associated with threaded fasteners is the accidentaldisassembly when pre-load is lost. When pre-load is lost, a standardfastener quickly vibrates out, causing the assembly to loosen.©1993-2006 Long-Lok Fasteners Corporation.

A threaded fastener of the prevailing torque type is frictionallyresistant to rotation due to a built-in wedge. Such fastener retains itslocking ability independent of axial tension or pre-load. Self-lockingfasteners of this type were developed to retain the advantage ofreusability while preventing the problems of accidental disassembly whenpre-load is lost. ©1993-2006 Long-Lok Fasteners Corporation.

Jam nuts, cotter pins, lock nuts, lock washers and similar devices alsoprevent the loss of the bolt or nut by back off but they result in addedweight, inconvenience and cost. They do not reduce the tendency tofatigue when loose. Further, the insecurity of conventional mechanicallocks is reason enough for most designers to reject them. Suchinsecurity arises from the frequency of split-type washers breaking,damage to surface areas caused by external locking devices, and theineffectiveness of such devices when adjustments are needed. ©1993-2006Long-Lok Fasteners Corporation.

A prevailing torque type fastener or self-locking fastener was developedto retain the advantage of reusability while preventing the problems ofaccidental disassembly when pre-load is lost. Self-locking fastenersvirtually eliminate the possibility of a bolted assembly coming apartduring operation. To achieve this benefit, the self-locking fastener hasto be properly designed, engineered and installed. Self-locking helpsmaintain a tight joint and also helps prevent fatigue failure in thejoint. Self-locking fasteners resist rotation on the first installationand on subsequent installations and removals. In addition, self-lockingfasteners also decrease the tendency of the fastener to fatigue byreducing the vibration transferred to the fastener. ©1993-2006 Long-LokFasteners Corporation.

One of the earliest methods of producing prevailing torque type lockingfeatures (also referred to as “patches” in the art) on externallythreaded fasteners was the “spray-on” nylon patch. In this type ofpatch, nylon resin is deposited on the threads of screws, which had beenpre-heated to a temperature range slightly above the melting point ofthe plastic powder, thus allowing the plastic powder to melt rapidlyupon contact with the hot threads. This mass of molten plastic was then“quenched” in a water/oil medium to cool the screws, leaving a depositof plastic firmly attached within a predetermined location of the screwthreads. This predetermined deposit of plastic is referred to as a“patch.”

To produce an effective patch the following principles must beconsidered: 1) transferring the plastic resin to the hot screws, 2)controlling the amount of powder to be deposited (patch geometry), and3) controlling the patch location on the screw.

Many techniques and methods have been employed over the years to applyplastic nylon resin to the hot screws in order to produce “locking”features or “patches”. Some obvious strategies included incorporating“gravity” and letting powder free-fall over the hot screw threads.Others have utilized shaking bars, spray bars, and spray nozzles poweredby compressed air. Due to the uncontrollable nature of the propelledpowder, devices, such as barriers, templates, and spray tips, have beenutilized. One method uses nozzles made from standard elongated coppertubing in an attempt to force the powder spray pattern to conform to thescrew thread profile.

In order to provide some consistency in the prevailing torquecharacteristics, control of the deposited plastic resin on the screwmust be achieved. Many techniques have been employed to control thelocation and geometry of the patches. The technique typically involvesstrategically located “jets” of air to prevent powder from contactingthe hot screw heads in areas where powder is unwanted (e.g. lead-in).The amount of patch material to be deposited is determined by the volumeof the powder contacting the threads and melting in place. Thecircumferential coverage is not typically considered a criticalcharacteristic of the patch, so the patch may typically range from 60°to a full 360° circumferential coverage. The typical specification limiton the height of the patch over the major diameter is 0.003 inches.

Rotation of the screws as they pass-by the point of powder applicationand various air-jets, are typically utilized to control the patchgeometry. The results are patches, which will yield prevailing torquewithin a pre-specified range.

Economics dictates what method is acceptable, since nylon resin powderis expensive and rework is costly. Another interesting dilemma isencountered when attempting to re-use powder that did adhere duringinitial application. Particles of the powder may have actually melted,but not adhered to the screw. When re-used, multiple melting of thepowder has been show to cause degradation of the resin properties. Theseproperties can affect prevailing torque characteristics.

SUMMARY OF INVENTION

The purpose of the plastic is to provide frictional resistance with themating threads when engaged, thus creating a desired resistance torotation of the screw, as it is assembled with the nut or threadedcomponent. The absence of patch material in the first one to two threadsis typically required in order to allow initial hand assembly of thescrews.

The plastic resin that does not contact the hot screw threads or moltenplastic is typically caught and re-claimed. Resin that finds its waypast the hot threads can account for over 75% of the powder passingthrough the system.

The three major components of the plastic resin patch applicationprocess are: 1) providing adequate patch volume, 2) providing one to twothread lead-in and proper patch length, and 3) dealing with significant“wasted resin.”

It would be desirable to be able to pre-determine the required patchgeometry (length×width×thickness) and control the lead-in with orificelocation adjustment. In such case, the need for supplemental air-jets,barriers and templates would be advantageously eliminated. Additionally,the ability to pre-determine the geometry of the powder mass would leadto minimizing wasted powder.

In accordance with one aspect of the present invention, a patchapplication system is provided comprising a powder application boothcomprising a shaft encoder, wherein the shaft encoder senses thepresence of the screw and sends a signal to a programmable logiccontroller to deliver a puff of air through the powder block to ejectthe powder onto the screw; a rotating disk to deliver the screw to thepowder application booth; an induction heating coil adjacent to therotating disk to heat the screw to a temperature that will cause theresin to melt upon contact with the heated screw; a controller toregulate the temperature of the induction heating coil; a bowl feederadjacent to the rotating disk to deliver the screw into a slot of therotating disk; a screw hopper to connected to the bowl feeder, whereinthe screw hopper contains a plurality of screws to be delivered to therotating disk by the bowl feeder; a screw ejector adjacent to therotating disk to eject the screw out of the slot; a parts dischargechute to catch the screw ejected from the slot; a cold water/oil quenchbelow the parts discharge chute to capture and cool the ejected screw,thereby solidifying the resin onto the screw and providing for safehandling.

The powder application booth preferably comprises a powder block totemporarily house the powder prior to ejection, a nozzle insert to guidethe powder onto the screw, a support stand to adjust the powder block tothe appropriate position relative to the screw for a desired patchlocation and size, and a powder cup to deliver the powder to the powderblock.

The powder application booth may further comprise a purge system toclean out unused powder, a micro air-switch valve to control a pulse ofair entering into the powder block, an air dryer to assure the air isdry prior to entering the powder block, an air filter to assure the airis clean prior to entering the powder block, a precision regulator toadjust the pressure of the air sent into the powder block, an aircompressor to provide the source of pressurized air, a programmablelogic controller electronically coupled to the micro air-switch valve tocontrol the duration the air-switch valve remains open, and a powderrecovery system located below the screw to capture powder that does notfuse with the screw.

These and other aspects of the invention will become apparent from areview of the accompanying drawings and the following detaileddescription of the invention.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a cross sectional view of an embodiment of the powderapplication booth.

FIG. 2A is a perspective view of an embodiment of the powder applicationbooth.

FIG. 2B is front view of an embodiment of the powder application booth.

FIG. 3 is another perspective view of an embodiment of the powderapplication booth.

FIG. 4A is a side view of a fastener with an applied patch.

FIG. 4B is a bottom view of a fastener with an applied patch.

FIG. 5 is a top view of an embodiment of the patch application system.

FIG. 6 is a perspective view of an embodiment of the patch applicationsystem.

BEST MODE FOR CARRYING OUT THE INVENTION

The detailed description set forth below in connection with the appendeddrawings is intended as a description of illustrated exemplaryembodiments and is not intended to represent the only forms in whichthese embodiments may be constructed and/or utilized. The descriptionsets forth the functions and sequence of steps for constructing andoperating the present invention in connection with the illustratedembodiments. However, it is to be understood that the same or equivalentfunctions and/or sequences may be accomplished by different embodimentsthat are also intended to be encompassed within the spirit and scope ofthe present invention.

The present invention is a patch application system comprising a powderapplication booth 100 to provide a self-locking fastener that isreusable while preventing the problems of accidental disassembly.

As shown in the embodiment of FIGS. 1 and 2A, the powder applicationbooth 100 may comprise a powder block 102 and a nozzle insert 104. Thepowder application booth 100 may further comprise a support stand 106, apowder cup 108, a micro air-switch valve 110, a precision regulator 112,an air compressor 114, and a programmable logic controller 116.

In one embodiment, the powder block 102 comprises a chamber 118, apowder ejection orifice 120, a powder entry orifice 122, and an air floworifice 124. Powder may be delivered into the chamber 118 through thepowder entry orifice 122 and the powder in the chamber 118 is ejectedonto a screw 400 through the powder ejection orifice 120 by a pulse ofair delivered through the air flow orifice 124 by an air compressor 114or the like. The powder ejection orifice 120, powder entry orifice 122,and air flow orifice 124 are generally circular. These orifices,however, can be any shape.

The powder is delivered to the chamber 118 through the powder entryorifice 122. The air flow orifice 124 and the powder ejection orifice120 are small enough that when powder is delivered to the powder entryorifice 122, very little powder spills over towards the air flow orifice124 or the powder ejection orifice 120. The weight of the powder comingthrough the powder entry orifice 122 should be sufficient to causeenough friction to facilitate immobilization of the powder within thechamber 118. The pulse of air can then eject a small quantity of powderthrough the powder ejection orifice 120 and onto the screw 400. Thechamber 118 can further comprise a well 126 where the powder mayaccumulate.

The nozzle insert 104 may be housed inside the powder ejection orifice120. The nozzle insert 104 is generally cylindrical in shape andcomprises an outer surface 128 and an inner surface 130. The outersurface 128 is substantially the same curvature as the powder ejectionorifice 120 such that the nozzle insert 104 fits tightly in the powderejection orifice 120. The inner surface 130 defines a cavity or gap 132through which the powder travels to exit the chamber 118. The gap 132 ispreferably truncated so as to form a rectangular slit as the opening.This truncated type opening facilitates a proper dispersion pattern ofthe powder. Specifically, as shown in FIG. 3, the rectangular slit orgap controls the vertical dispersion Y′ of the powder while maintaininga degree of freedom for the horizontal dispersion X′ of the powder. FIG.4A shows a typical screw 400 comprising a head 406 and a threaded neck408 with a patch 404 applied.

In one embodiment, the nozzle insert 104 is created by machining a gapof the desired dimensions. In another embodiment, the nozzle insert 104may be made of different component parts.

As shown in FIG. 4B, the circumferential patch coverage may range fromapproximately 30° to a full 360° circumferential coverage. Preferably,the circumferential patch coverage ranges from approximately 60° toapproximately full coverage. Circumferential patch coverage is achievedby allowing the powder to melt on the fastener and allowing the meltedpowder to flow around the threads before solidifying. Therefore, it isunnecessary to rotate the screws as they pass through the powderapplication booth.

The thickness of the patch 404 is less than approximately 0.01 inches.In another embodiment, the thickness of the patch 404 is less than 0.003inches. In another embodiment, the maximum diameter of the patch 404 isless than approximately 0.003 inch over the diameter of the neck 408 ofthe screw 400. The length of the patch 404 may vary with the size of thescrew 400. The length of the patch 404 may be sufficient to cover allthe threads of the screw except for a lead-in 402. Preferably, thelength of the patch 404 is sufficient to cover approximately 3 toapproximately 5 threads. The lead-in 402 is at least 1 to 2 threads.

As shown in FIG. 4A, controlling the vertical dispersion Y′ facilitatesthe creation of a lead-in 402 at the tip of the screw 400 as well as thepatch length. In one embodiment, the nozzle insert 104 is created by twosemi-circular pegs fitted inside the powder ejection orifice 120 suchthat a gap 132 exists between the two semi-circular pegs. The gap 132can be in the shape of a rectangular slit so as to provide a narrowvertical dimension of the powder ejection orifice 120. The size of thegap 132 and the length of the powder ejection orifice 120 may bemodified by changing the length and thickness of the insert nozzle 104.One method of changing the dimensions of the insert nozzle 104 is toreplace one insert nozzle 104 with another insert nozzle with differentdimensions. Another method for changing the dimensions of the insertnozzle 104 is to add components of varying thicknesses inside the gap132. For example, thin rectangular slabs may be inserted into the gap132. In another embodiment, the nozzle insert may have moveable partsthat can expand or contract to change the dimensions of the nozzleinsert 104. The desired dimensions of the gap 132 and the nozzle insert400 will vary depending on such factors as the size of the screw 404,the amount of pressure applied to the air pulse, the duration of the airpulse, and the amount of powder used.

In another embodiment, the nozzle insert 104 may be replaced with apowder ejection orifice 120 with movable parts such that the size of thepowder ejection orifice 120 may be modified.

The support stand 106 provides support to the powder block 102. In oneembodiment, the support stand 106 is adjustable so as to allow movementof the powder ejection orifice 120 in an up and down direction, aside-to-side direction, and a forward and backward direction. Thesedegrees of freedom allow for proper positioning of the powder ejectionorifice 120 relative to the screw so as to form a proper patch 404location and size.

In one embodiment, the powder cup 108 is attached to the powder entryorifice 122 of the powder block 102. The powder cup 108 may be in theshape of a funnel and comprise an open top 140 through which the powdercan be added and an open bottom 138 through which the powder can exitinto the powder block 102.

The micro air-switch valve 110 acts as a quick action gate inconjunction with the precision regulator 112 and the air compressor 114to control a pulse of air entering into the powder block 102. The microair-switch valve 110 controls the duration of the air flow. The microair-switch valve 110 can be adjusted so as to increase or decrease theduration of time of the air flow as well as duration of time theair-switch valve 110 remains closed in between pulses. The duration ofair flow may be from approximately 0.01 second to approximately 0.5second. In one embodiment, the duration of air flow is approximately 0.1second to approximately 0.3 second.

The precision regulator 112 adjusts the amount of pressure of the airsent into the powder block 102. The air compressor 114 creates aboutapproximately 120 pounds per square inch (psi) of pressurized air. Whenthis pressurized air reaches the precision regulator 112, the precisionregulator 112 can modify the amount of pressure from approximately 0 psito approximately 10 psi. In one embodiment, the pressure of the air isfrom approximately 0.5 psi to approximately 5 psi.

The programmable logic controller 116 is electronically coupled to themicro air-switch valve 110 to control the duration the air-switch valve110 remains open. The programmable logic controller 116 may also receiveinput from an encoder 134. The encoder 134 senses whether a screw isproperly aligned with the nozzle insert 104. Upon detection of properalignment, the encoder 134 sends a signal to the programmable logiccontroller 116. The programmable logic controller 116 then sends asignal to the micro air-switch valve 110 to open and close for a desiredduration to spray the screw 400.

The powder application booth 100 may further comprise a powder feeder136. The powder feeder 136 may be attached to the open bottom 138 of thepowder cup 108 through which the powder is channeled into the powderblock 102 to deposit a predetermined amount of the powder into thepowder block 102. The predetermined amount varies depending on a varietyof parameters such as the size of the screw 400, the patch 404 size, thedistance the insert nozzle is away from the screw, the air pressure, andthe duration of air flow. Each of these parameters is determinedempirically. Various parameters can be changed independently and thedata collected to generate a database of which parameter combinationsresult in the desired patch geometry. A desired patch geometry covers atleast 2 threads on the neck of a screw and leaves a lead-in of at leastone thread. In one embodiment, the desired patch covers approximately3-5 threads on the neck of a screw and leaves a lead-in of approximately1-2 threads.

In another embodiment, the powder application booth 100 may furthercomprise a standard purge system. The purge system cleans out unusedpowder in the powder application booth 100.

In another embodiment the powder application booth 100 may furthercomprise an air dryer 142. The air dryer 142 dries the pressurized airbefore being pulsed to assure the air is dry prior to entering thepowder block 102.

In another embodiment, the powder application booth 100 may furthercomprise an air filter 144. The air filter 144 assures the air is cleanand free of debris prior to entering the powder block 102 as debris cancause problems in the formation of the patch.

In another embodiment the powder application booth 100 may furthercomprise a standard powder recovery system 154. The powder recoverysystem 154 is located below the screw 400 to capture powder that doesnot fuse with the screw 400. The powder recovery system 154 comprises apowder system cabinet 146 to house a vacuum system 152 and a powderchiller/filter 150. The vacuum system 152 provides a suction to captureresin that is ejected through the nozzle insert 104 that either did notremain on the screw or that missed the screw entirely. The powderchiller/filter 150 cools the powder and filters out coagulated powderlarger than a single grain of powder as well as other debris from theair. In particular, powder particles may come in contact with the screwand begin melting and coalescing with each other. The particles may not,however, stay on the screw but rather fall off. These coalesced powderparticulates would be captured by the powder recovery system 154.However, the coalesced powder would be captured at the powderchiller/filter 150 and discarded as particulates of relatively largesize may not be reusable.

The patch application system may further comprise an encoder 134, arotating disk 500, an induction heating coil 502, a load coiltransformer 504, a bowl feeder 600, a screw hopper 602, a screw ejector506, a parts discharge chute 508, and a cold water/oil quench 510.

The shaft encoder 134 senses the presence of the screw and sends asignal to the programmable logic controller 116 to deliver a puff of airthrough the powder block 102 to eject the powder onto the screw 400.

The rotating disk 500 delivers the screw 400 to the powder applicationbooth 100. The rotating disk 500 is generally circular and comprises aplurality of apertures 512 to hold a plurality of removable slots 514configured to accommodate a plurality of screws. The plurality ofremovable slots 514 are larger than the neck 408 of the screw 400 butsmaller than the head 406 of the screw 400 so that the screw 400 canhang vertically by the head 406 inside the slot 514. The plurality ofremovable slots 514 can range in size so as to accommodate screws ofdifferent sizes. Therefore, the powder application booth 100 can beconfigured to spray powder onto a particular sized screw 400. Whencompleted, the removable slots 514 can be replaced with removable slots514 of a desired size for a different size screw. The powder applicationbooth 100 can be configured for the new sized screw to spray theappropriate amount of powder at the appropriate location onto the newsized screw.

In another embodiment, the apertures 512 can hold the screws 400. Toaccommodate screws of a different size, a second rotating disk 500 withapertures 512 of a desired size can replace the first rotating disk 500.Therefore, rather than changing each aperture 512, a single rotatingdisk 500 can be changed when switching to a screw of a different size.

The induction heating coil 502 is located adjacent to the rotating disk500 and the powder application booth 100. The rotating disk 500 sendsthe screw 400 through the induction heating coil 502 where the inductionheating coil 502 heats the screw 400 to a temperature that will causethe powder to melt upon contact with the heated screw 400. The rotatingdisk 500 then delivers the heated screw 400 to the powder applicationbooth 100 where the powder is pulsed onto the heated screw 400.

The RF generator and controller 148 regulates the temperature of theinduction heating coil 502, so as to generate enough heat to heat ascrew 400 of a particular size to the appropriate temperature during thetime it takes for the screw to pass through the induction coil 502. TheRF generator and controller 148 controls the load coil transformer 504,via coaxial leads 604, to regulate the temperature of the inductionheating coil 502.

As shown in FIG. 6, the bowl feeder 600 may be adjacent to the rotatingdisk 500 and delivers the screw 400 into the slot 514 of the rotatingdisk 500. The screw hopper 602 allows a plurality of screws 400 to beadded to the to the bowl feeder 600. Together, the bowl feeder 600, thescrew hopper 602, and the rotating disk 500 allow for automated deliveryof a large quantity of screws to the powder application booth 100.

The screw ejector 506 is located adjacent to the rotating disk 500 toeject the screw out of the slot 514. The screw 400 is ejected into theparts discharge chute 508. The parts discharge chute 508 sends the screw400 to the cold water/oil quench 510 located below the parts dischargechute 508 to cool and quench the ejected screw, thereby solidifying theresin onto the screw and providing for safe handling

In use, the method of applying a plastic resin patch 404 onto a screw400 comprises the steps of pre-determining a desired patch geometry on ascrew 400; selecting a nozzle insert 104 dimensioned to provide thepre-determined patch geometry; adjusting a distance Z′ between thenozzle insert 104 and the screw 400 to create a desired lead-in 402;selecting an amount of powder required to produce the desired patchgeometry while minimizing waste; selecting a duration and an amount ofair pressure to pulse onto the powder; heating the screw 400 to atemperature sufficient to melt the powder; pulsing air at the selectedduration and air pressure through the powder to cause the powder toeject onto the screw 400 and melt onto the screw; quenching the powdermelted onto the screw 400 to solidify the powder; comparing a resultingpatch geometry with the desired patch geometry; adjusting at least oneparameter selected from the group consisting of the nozzle insert 104,the distance Z¹ between the nozzle insert 104 and the screw, the amountof powder, the duration of the air pulse, and the air pressure; andrepeating the aforementioned steps until the desired patch geometry isachieved for a screw of a particular size. This process can be repeatedfor screws 400 of various sizes and a database can be kept with therelevant information. Preferably, this information is kept on theprogrammable logic controller 116 so that inputting a screwspecification will automatically configure the resin application systemto the appropriate specifications.

Once the proper specifications are known for a screw 400 of a particularsize the plastic resin can be applied onto a screw 400 by selecting ascrew size; selecting a predetermined nozzle insert 104 to produce adesired patch 404 on a screw 400; adjusting the nozzle insert 104 to apredetermined distance Z′ from the screw 400; selecting a predeterminedair pressure and a predetermined pulse duration; and automaticallypulsing a puff of air at the predetermine pressure through a powderblock 102 to cause a powder to eject through the insert nozzle 104 ontothe screw 400 to form a predetermined patch 404 on the screw 400.

The predetermined distance Z′ between the screw and the nozzle insert104 is approximately 0.001 inch to approximately 1 inch. In anotherembodiment, the predetermined distance Z′ between the screw and thenozzle insert 104 is approximately 0.1 inch to approximately 0.5 inch.

The method of applying powder resin onto a screw can further comprisethe steps of continuously rotating a plurality of screws on a rotatingdisk 500 comprising a plurality of removable slots 514; passing theplurality of screws through an induction coil 502 to heat the screws 400to a temperature above the melting point of the powder; automaticallydetecting when the screw 400 is aligned with the insert nozzle 104; andsending a signal to a programmable logic controller 116 to automaticallypulse the puff of air through the powder block 102 to cause the powderto eject through the nozzle insert 104 onto the screw 400, therebycoating the screw 400 with the powder.

Additional steps include removing the screw 400 coated with the powderfrom the rotating disk 500 and quenching the screw coated with thepowder in a water/oil solution 510.

The entire process can be automated by providing a screw hopper 602 toprovide an unlimited supply of screws 400 and providing a bowl feeder600 to transfer the plurality of screws 400 from the screw hopper 602 tothe rotating disk 500, such that the plurality of screws are insertedinto the removable slots 514 of the rotating disk 500 with the head 406of the screw 400 on top and the neck 408 of the screw fitting throughthe removable slots 514.

Undoubtedly, numerous variations and modifications of the invention willbecome readily apparent to those familiar with producing self-lockingfasteners. Accordingly, the scope of the invention should not beconstrued as limited to the specific embodiments depicted and described,but rather is defined in the claims appended hereto.

INDUSTRIAL APPLICABILITY

This invention may be industrially applied to the development,manufacture, and use of an apparatus for and a method of producingself-locking fasteners.

1. A patch application system, comprising a powder application booth,the powder application booth comprising: (a) a powder block comprising achamber, a powder ejection orifice, a powder entry orifice, and an airflow orifice, wherein a powder is delivered into the chamber through thepowder entry orifice and the powder in the chamber is ejected onto ascrew through the powder ejection orifice by a pulse of air deliveredthrough the air flow orifice; (b) a nozzle insert housed inside thepowder ejection orifice, the nozzle insert comprising two semi-circularpegs fitted inside the powder ejection orifice such that a gap existsbetween the two semi-circular peg, wherein the gap narrows a verticaldimension of the powder ejection orifice; (c) a support stand to supportthe powder block, the support stand being adjustable so as to move thepowder ejection orifice in an up and down direction, a side-to-sidedirection, and a forward and backward direction, to position the powderejection orifice in relation to the screw so as to form a proper patchlocation; (d) a powder cup attached to the powder entry orifice of thepowder block, the powder cup being in a shape of a funnel and comprisingan open top through which the powder can be added and an open bottomthrough which the powder can exit into the powder block; (e) a microair-switch valve to control the pulse of air entering into the powderblock; (f) an air dryer to dry the air prior to entering the powderblock; (g) an air filter to clean the air prior to entering the powderblock; (h) a precision regulator to adjust an air pressure of the pulseof air sent into the powder block, wherein the air pressure is fromapproximately 0.5 psi to approximately 10 psi; (i) an air compressor toprovide a source of the pulse of air, wherein the air pressure at thesource of the pulse of air is 120 psi; (j) a programmable logiccontroller electronically coupled to the micro air-switch valve tocontrol a duration the micro air-switch valve remains open, wherein theduration the micro air-switch valve remains open is 0.01 second to 0.5second; (k) a powder recovery system located below the screw to capturean unused powder that does not fuse with the screw, the powder recoverysystem comprising a vacuum system and a powder chiller/filter, thevacuum system providing a suction to capture the unused powder, thepowder chiller/filter filtering out the unused powder larger than asingle grain of the powder; and (l) a shaft encoder, wherein the shaftencoder senses a presence of the screw and sends a signal to theprogrammable logic controller to deliver the pulse of air through thepowder block to eject the powder onto the screw.
 2. A patch applicationsystem, comprising: (a) a powder application booth comprising: (i) apowder block comprising a chamber, a powder ejection orifice, a powderentry orifice, and an air flow orifice, wherein a powder is deliveredinto the chamber through a powder entry orifice and the powder in thechamber is ejected onto a screw through the powder ejection orifice by apulse of air delivered through the air flow orifice, (ii) a nozzleinsert housed inside the powder ejection orifice, the nozzle insertcomprising a peg fitted inside the powder ejection orifice to narrow avertical dimension of the powder ejection orifice, (iii) a microair-switch valve to control the pulse of air entering into the powderblock, (iv) a precision regulator to adjust an air pressure of the pulseof air sent into the powder block, (v) an air compressor to provide asource of the pulse of air, (vi) a programmable logic controllerelectronically coupled to the micro air-switch valve to control aduration the micro air-switch valve remains open, (b) an inductionheating coil adjacent to a rotating disk, wherein the induction heatingcoil heats the screw to a temperature that will cause the powder to meltupon contact with a heated screw; and (c) a cold water/oil quenchlocated below a parts discharge chute to capture and cool an ejectedscrew, thereby solidifying the resin onto the screw.
 3. The patchapplication system of claim 2, further comprising (a) a powder cupattached to the powder entry orifice of the powder block, the powder cupcomprising an open top through which the powder can be added and an openbottom through which the powder can exit into the powder block; and (b)a powder feeder attached to the open bottom of the powder cup throughwhich the powder is channeled into the powder block to deposit apredetermined amount of powder into the powder block.
 4. The patchapplication system of claim 2, further comprising a support stand tosupport the powder block, the support stand being adjustable so as tomove the powder orifice in an up and down direction, a side-to-sidedirection, and a forward and backward direction, to position the powderorifice in relation to the screw so as to form a proper patch location.5. The patch application system of claim 2, further comprising: (a) arotating disk, wherein the rotating disk delivers the screw to thepowder application booth; and (b) a plurality of removable slotsconfigured to accommodate the screw, wherein the plurality of removableslots are larger than a neck of the screw, but smaller than a head ofthe screw so that the screw can hang vertically by the head with theneck hanging below the head.
 6. The patch application system of claim 2,further comprising: (a) a shaft encoder, wherein the shaft encodersenses a presence of the screw and sends a signal to the programmablelogic controller to deliver a puff of air through the powder block toeject the powder onto the screw; (b) a bowl feeder adjacent to therotating disk, wherein the bowl feeder delivers the screw into theplurality of removable slots of the rotating disk; (c) a screw hopperconnected to the bowl feeder, wherein the screw hopper contains theplurality of screws to be delivered to the rotating disk by the bowlfeeder; (d) a screw ejector adjacent to the rotating disk, wherein thescrew ejector ejects the plurality of screws out of the plurality ofremovable slots after application of the powder; and (e) a partsdischarge chute to catch the screw ejected from the slot.
 7. A patchapplication system, comprising a powder application booth, the powderapplication booth, comprising: (a) a powder block comprising a chamber,a powder ejection orifice, a powder entry orifice, and an air floworifice, wherein a powder is delivered into the chamber through a powderentry orifice and the powder in the chamber is ejected onto a screwthrough the powder ejection orifice by a pulse of air delivered throughthe air flow orifice; and (b) a means for narrowing a vertical dimensionof the powder ejection orifice.
 8. The patch application system of claim7, wherein the means for narrowing the vertical dimension of the powderejection orifice comprises a nozzle insert housed inside the powderejection orifice
 9. The patch application system of claim 8, wherein thenozzle insert comprises a peg fitted inside the powder ejection orifice.10. The patch application system of claim 9, wherein the nozzle insertcomprises two pegs fitted inside the powder ejection orifice, such thata gap exists between the two pegs, wherein the gap narrows the verticaldimension of the powder ejection orifice.
 11. The patch applicationsystem of claim 7, further comprising an induction heating coil to heatthe screw to a temperature that will cause the powder to melt uponcontact with a heated screw.
 12. The patch application system of claim7, further comprising a quench located below a parts discharge chute tocapture and cool an ejected screw, thereby solidifying the resin ontothe screw.
 13. The patch application system of claim 7, furthercomprising a powder cup attached to the powder entry orifice of thepowder block, the powder cup comprising a top through which the powdercan be added and a bottom through which the powder can exit into thepowder block.
 14. The patch application system of claim 13, furthercomprising a powder feeder attached to the open bottom of the powder cupthrough which the powder is channeled into the powder block to deposit apredetermined amount of powder into the powder block.
 15. The patchapplication system of claim 7, further comprising an adjustable supportstand to support the powder block to position the powder orifice inrelation to the screw so as to form a proper patch location.
 16. Thepatch application system of claim 7, further comprising a rotating disk,wherein, the rotating disk delivers the screw to the powder applicationbooth.
 17. The patch application system of claim 16, further comprisinga plurality of removable slots on the rotating disk and configured toaccommodate the screw, wherein the plurality of removable slots arelarger than a neck of the screw, but smaller than a head of the screw sothat the screw can hang vertically by the head with the neck hangingbelow the head.
 18. The patch application system of claim 17, furthercomprising: (a) a bowl feeder adjacent to the rotating disk, wherein thebowl feeder delivers the screw into the plurality of removable slots ofthe rotating disk; and (b) a screw hopper connected to the bowl feeder,wherein the screw hopper contains the plurality of screws to bedelivered to the rotating disk by the bowl feeder.
 19. The patchapplication system of claim 16, further comprising: (a) a screw ejectoradjacent to the rotating disk, wherein the screw ejector ejects theplurality of screws out of the rotating disk after application of thepowder; and (b) a parts discharge chute to catch the screw ejected fromthe slot.
 20. The patch application system of claim 7, furthercomprising a shaft encoder, wherein the shaft encoder senses a presenceof the screw and sends a signal to a programmable logic controller todeliver a puff of air through the powder block to eject the powder ontothe screw.